一次春季混合性大风诊断分析

Diagnostic Analysis of A Mixed Gala in Spring

针对2012年4月2-3日一次混合性大风过程,采用NECP再分析资料、多普勒雷达资料进行分析,结果表明,本次过程是由黄海低压和冷空气共同影响的结果,大风前期是一次急行冷锋过程,锋线附近发生了强对流天气,强对流的辐散气流加大了风速;而黄海气旋的爆发性发展和冷空气相结合是大风后期维持的主要原因,其中,低层强斜压性和高空暖平流有利于低压的发展,而高空正涡度平流和气旋移动到高空急流出口区的左侧促成了低压的爆发性发展。

In this paper,we use NECP reanalysis data and Doppler Radar data to comprehensively analyse a severe convection weather event under the effect of thick cold air on 2-3 April 2012. The results show that this strong gala process was combined influences by the development of Huanghai cyclone and the cold air gala. In early stage it was a rushed Cold-Front, we found that the severe convective weather was happened around the frontal line, the wind velocity speeded as the divergence flow which came from the server convec-tion. However, the combination of the fulminic development of the Huanghai cyclone and the gradient of the cold air was the main cause of this strong gala lasted in its later stage. Among them ,the lower strong baroclin-icity and the upper warm advection favour the development of the ground cyclone. Meanwhile, the upper posi-tive vorticity advection and the cyclone′s moving to the left side of upper air jet stream exit area had made great contribution to the fulminic development of the Huanghai cyclone.